package com.tssup.fesco.common.security;

import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;


public class AES128Encryption {

	/**
	 * 加密
	 * @param content
	 * @param password
	 * @return
	 */
	public static String encrypt(String content, String password) {  
        try {             
                KeyGenerator kgen = KeyGenerator.getInstance("AES");  
                kgen.init(128, new SecureRandom(password.getBytes()));  
                SecretKey secretKey = kgen.generateKey();  
                byte[] enCodeFormat = secretKey.getEncoded();  
                SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");  
                Cipher cipher = Cipher.getInstance("AES");// 创建密码器  
                byte[] byteContent = content.getBytes("utf-8");  
                cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化  
                byte[] result = cipher.doFinal(byteContent);  
                return parseByte2HexStr(result); // 加密  
        } catch (NoSuchAlgorithmException e) {  
                e.printStackTrace();  
        } catch (NoSuchPaddingException e) {  
                e.printStackTrace();  
        } catch (InvalidKeyException e) {  
                e.printStackTrace();  
        } catch (UnsupportedEncodingException e) {  
                e.printStackTrace();  
        } catch (IllegalBlockSizeException e) {  
                e.printStackTrace();  
        } catch (BadPaddingException e) {  
                e.printStackTrace();  
        }  
        return null;  
	}  
	
    /**解密 
     * @param content  待解密内容 
     * @param password 解密密钥 
     * @return 
     */  
    public static byte[] decrypt(String content, String password) {  
            try {  
	                KeyGenerator kgen = KeyGenerator.getInstance("AES");  
	                kgen.init(128, new SecureRandom(password.getBytes()));  
	                SecretKey secretKey = kgen.generateKey();  
	                byte[] enCodeFormat = secretKey.getEncoded();  
	                SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");              
	                Cipher cipher = Cipher.getInstance("AES");// 创建密码器  
                    cipher.init(Cipher.DECRYPT_MODE, key);// 初始化  
                    byte[] result = cipher.doFinal(parseHexStr2Byte(content));  
                    return result; // 加密  
            } catch (NoSuchAlgorithmException e) {  
                    e.printStackTrace();  
            } catch (NoSuchPaddingException e) {  
                    e.printStackTrace();  
            } catch (InvalidKeyException e) {  
                    e.printStackTrace();  
            } catch (IllegalBlockSizeException e) {  
                    e.printStackTrace();  
            } catch (BadPaddingException e) {  
                    e.printStackTrace();  
            }  
            return null;  
    }  
    
    public static String parseByte2HexStr(byte buf[]) {  
        StringBuffer sb = new StringBuffer();  
        for (int i = 0; i < buf.length; i++) {  
                String hex = Integer.toHexString(buf[i] & 0xFF);  
                if (hex.length() == 1) {  
                        hex = '0' + hex;  
                }  
                sb.append(hex.toUpperCase());  
        }  
        return sb.toString();  
    } 
    
    public static byte[] parseHexStr2Byte(String hexStr) {  
        if (hexStr.length() < 1) {
            return null;
        }
        byte[] result = new byte[hexStr.length()/2];  
        for (int i = 0;i< hexStr.length()/2; i++) {  
                int high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);  
                int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);  
                result[i] = (byte) (high * 16 + low);  
        }  
        return result;  
    }
    

}
